SO FLORA HISTORICA. 



Keren of the Dutch. The modern name of Chei- 

 ranthus for the Wall-flower and the Stock was given 

 by Linnaeus, who gave it this Greek name from 

 j^eif, a hand, and civ9os, a flower, which he derived 

 from the Arabic Keiri. It was by the same learned 

 botanist placed in the natural order Cruciformes, 

 because the flowers have only four petals, which 

 expand in the form of a cross. It is also, and more 

 correctly, ranked in the natural order Siliquosce, 

 because the seed is contained in a siliqua (pod.) 

 The silique is a pod, consisting of two valves, and 

 generally one dissepiment, extending its whole 

 length, and the seeds are fixed on both sutures ; it 

 differs from the legume (legumen), where the seeds 

 are fixed on one and the same suture, but alternately 

 upon the two valves. 



The Wall-flowers which grow out of the cre- 

 vices of old buildings are of a much hardier nature 

 than those of the garden, for as they can receive 

 but little moisture by the fibres of their roots, their 

 stem becomes firm and woody, and able to bear the 

 frost without injury, whereas those cultivated in 

 the garden become succulent, and, consequently, 

 more susceptible of cold. The two principal va- 

 rieties of Wall-flower are the yellow, and the red 

 or bloody. These, by intermixture of impregna- 

 tion, have created numerous trivial varieties, as the 

 yellow striped with a reddish brown, or the red 



